Wednesday, July 30, 2014

The rock doc: Rapid chemistry when it matters most

July 8, 2010 |

Special to the Democrat

The last time I went to Nevada, I stood on the edge of an enormous open-pit mine at noon. The whistle blew. Then the pit erupted in explosive power enough to make the Earth rumble.

ÒI always like to watch it,Ó said the geologist giving me the tour. ÒIt looks like the rocks down there just get ÔfluffyÕ when they are blasted apart.Ó

We had visited the floor of the great pit, picking up rocks, squinting at them through hand-lenses, and hammering on them. The strong Nevada wind was blowing all day and by the end of it all I was filthy, to say the least.

Although I donÕt know for sure, if I had gone directly from the mine to an airport, I might not have been able to board a commercial plane. The reason is that some airports employ ÒsniffersÓ that can detect explosives, even in trace amounts.

Roughly speaking, there are two kinds of sniffers. First, there are the type with wet noses you can train with dog-treats to signal the presence of a wide range of materials, from drugs to explosives to produce.

Second, there are sniffers that are man-made devices that are also exquisitely good at detecting just a few particles of various materials for which they are designed and calibrated. The second, mechanical type are not as cute as beagles, to be sure, and they donÕt move around a busy airport lobby on their own four feet, following their noses. But, on the positive side, the man-made sniffers donÕt get pooped out in mid-afternoon like dogs (and me).

Unfortunately, no sniffers of either kind appear to have been on duty last Christmas when the Òunderwear bomberÓ tried to blow a jetliner out of the skies over our Midwest. If the authorities had used sniffers on Umar Farouk Abdulmutallab, IÕm told they would have had a good chance of detecting the explosive before he was allowed to board the first plane of his long travels.

I spoke recently about all this with Prof. Herbert Hill of Washington State University. For many years now, he has been in the field of ion mobility spectrometry Ñ IMS Ñ (thatÕs the fancy term for the broad set of lab devices that can include the man-made sniffers in airports today). IMS works by giving an electrical charge to small particles, and then watching how they move from one charged plate to another.

Hill is an analytical chemist: somebody who wants to identify chemical samples. He got started in his field partly due to his interest in being able to detect tiny amounts of pesticide in stream water or contamination in drug manufacturing. IMS is his favorite analytic device, his Òbaby.Ó

HillÕs laboratory is made of room after room with IMS devices, each one a research unit, not a commercial device, and each set up for a different purpose. While not as interesting as beagles to me (IÕm a dog person Ð what can I say), the devices are amazing in what they can do. And they have come a long way.

When Hill first worked with IMS, it took about four hours to get a full reading on a single sample. It now takes less than a second Ð which is why IMS has become so useful in real-world applications like airports. Clearly, in the day-to-day world, we need systems that work fast, and that make as few errors, one way or another, as possible.

ItÕs interesting to note that what counts as an ÒerrorÓ is complex. If an IMS sniffer (or a beagle, for that matter) pulls a geologist out of an airplane line just for having been around explosives, thatÕs a Ògood hitÓ in the sense that the sniffer is legitimately detecting explosives. But itÕs not usually useful security information, and is likely to delay not just one rock-head but potentially a whole planeload of people.

As you might guess, HillÕs former students are in industry, government and Homeland Security. Some of them are likely laboring today to try to keep our airplanes in the skies.

Even though they could pull me aside with their sniffers, I wish them the very best.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. Follow her on the Web at and on Twitter @RockDocWSU. This column is a service of the College of Sciences at Washington State University.



E. Kirsten Peters



District 2 candidate statements tell of goals

By Dawn Hodson | From Page: A1

Sand Fire nears containment: 66 structures destroyed

By Cole Mayer | From Page: A1 | Gallery

Schedule for Highway 50 blasting closures

By News Release | From Page: A3

Tails wagging over dog park approval

By Julie Samrick | From Page: A3

Quarter-acre fire in Kelsey

By Rebecca Murphy | From Page: A3



My Turn: Privatization of public services

By Mark Belden | From Page: A4

Policy book

By Mountain Democrat | From Page: A4



Piano replaced

By Letters to the Editor | From Page: A5

Comments sign-in policy

By Letters to the Editor | From Page: A5, 1 Comment

Save the Guinea Worm

By Letters to the Editor | From Page: A5, 1 Comment

Large bangs

By Letters to the Editor | From Page: A5, 2 Comments

Private property gets no respect

By Letters to the Editor | From Page: A5, 2 Comments

District 2 supervisorial special election

By Letters to the Editor | From Page: A5, 4 Comments

GDPUD management report

By Letters to the Editor | From Page: A5



Ex-Bruin lends a helping hand

By Steven Shaff | From Page: A8 | Gallery

Sierra Sharks finish middle of the pack

By Democrat Staff | From Page: A8

Roundup: July 29, 2014

By Democrat Staff | From Page: A8

Taz pull through for SSL trophy

By Patty Pope | From Page: A8



Nuns discover a pleasant place

By Lexi Boeger | From Page: B1 | Gallery

Bargains can be found everywhere

By Democrat Staff | From Page: B2 | Gallery

At a glance: Game time

By Mimi Escabar | From Page: B2

Barbecue dinner to benefit Blue Star Moms

By Mount Aukum Winery | From Page: B2

Stagecoach story takes riders on a trip

By Wendy Schultz | From Page: B3

Help needed to make cool ties

By Sew 4 | From Page: B3

Stroke and osteoporosis screenings planned

By Life Line Screening | From Page: B3

Gold Rush Days activities cancelled this year

By Sacramento Convention And Visitors Center | From Page: B4

Master Food Preservers: Tomato time

By Monique Wilber | From Page: B4

Sacramento area museums offer summer fun

By Sacramento Association Of Museums | From Page: B5

Build an author platform at the Library

By El Dorado | From Page: B5



Weather stats 7-29-14

By Michael Raffety | From Page: A2

Building permits 6/2-6/2014

By Michael Raffety | From Page: A2Comments are off for this post

Crime Log: July 17

By Cole Mayer | From Page: A2



Merlyn Wilbur Adams

By Contributor | From Page: A2

Wallace Murrel Thomas

By Contributor | From Page: A2


Real Estate




Women’s Health

Love the skin you’re in

By Noel Stack | From Page: WH4

Dump stress and improve your health, productivity

By Wendy Schultz | From Page: WH7Comments are off for this post

Women’s Health Expo

By Marshall Medical | From Page: WH8

Find the confidence you need to fight back

By Special to the Democrat | From Page: WH12

Our choices directly affect our health

By Special to the Democrat | From Page: WH14

They’re NOT your mother’s hearing devices!

By Marshall Medical | From Page: WH17